Demountable  x t tread por pneumatic tikes



M-MAH 1:;

Jan. 9, 1923.

M. A. SHOTWELL. DEMOUNTABLE TREAD FOR PNEUMATIC T RES.

FILED A G. 28, 1922.

l oliented Jan. 9,

UNITED STATES MARCUS SHOTWEILL, OF QI'IICAGO, IILILINOIS,

DEMOUNTAIKLE THREAD FOR PNEUMATIC [Elli/135;.

Application filed August 28, 1922. Serial No. 534,835.

1 '0 (oil 40/1011) it may com/cm 13c it lmoivn that I, Marcos A. SLI'O'DWMLL, a citizen ol the United l'l'tates, residing at Chicago, in the county of Cook and State of lllinois, have invented certain new and useful linprove ncnts in Demountable ilreads forPneumatic 'lir oi? Which the following .'s a s iecilication, rel' rence being had to the accompanying drawings.

This invention relates to pneumatic tires, and aarticularly to the treads thereof.

The general object of my invention is to provide a cleinountable tread, that is one which may be readily applied to a pneumatic tire or readily removed therefrom and which, when in place upon the tire and the tire inflated, Will be held firmly in place against any lateral. or longitudimil rl A. futlun. ob' ,t is to rom .12 a cmistruction ol" this kind oi? extreme sin'uglicity and effectivemess, and to provide a tread of this character whichwill lessen the cost of main.- taining tires, and to n.'ovide a detachabhl tread which is made up oi? a rubber tread portion proper andlabric layers which are vulcanized to the tread portionproper.

A still further object is to prwlde a denioulitable and. detachable tread of this char acter having longitudinally extending Wires embedded. in the fabric portion of the tread, which Wires are so disposed that they will form circumiierentially extending ridges or ribs upon the inner :liace ol'" the llG'l'IlOlU'llitllJlG tread. which Will grip the phery oi the carcass oil? the pneul'natic tire and hold. the demountable tread from any lateral slipping.

Another object is to provide in a demount able tread oil the character stated a circun1- ferentially extending band which will preven t any expansion of the tread.

Still al'lother object is to so orl'n this doinountable tread that it will hold by suction on the tire,

Other objectsw'ill appear in the course 0' the following; description.

' invention illustrated in the accent "a {Wll l. I is an elevati.

nry demoiuitable or." detachable tread applied tl'icnr-ito the treai'l being broken away at two 'ioints;

Figure 2 is fragmentary sectional. poi spoctive of the tread, the tire being shown in dotted lines;

Figure 3 is a sectional View through the tire and through the tread.

mountable tread so that to Chi layers oil 'labric which are adapted to he portion. 10 while l2 designates on inner lininn oi? relativley thin rubber.

Embedded between the laniinations or layers of fabric 11. on the median line of the tire is a circiun'l e"entially eatendi steel. hand 13 constituting a circuinferentially e:.:- tending reinforcement which prevents the deinoui'itable tread ttrorn en'par cg. Einbedded between the layers oil 'lfabi I ll and the rubber lining; l9 a plurality oil? circuinitercntially tending; Wires let 'lhese Wires i l. cause ribs jlli to he ili'm'ined in the rubber lining, these ribs t tending circuml erentially and bearing; directly agains-it the tire carcass i l "lhe circuin'terentially ertending wires l/l are gradually l lll lian1- eter toward the lateral may 1, ol? the dewires hohl the tread transversely concave as to lit closely the transverse convexity oi. the tire carcass. ".lllnls this deinountable triad. has a normal. transverse convexity and ism cl? course, annular: in :liorrn. The rubber tread potion 10, the fabric layers ll. and the rubber lining 12 are all wilcanized to each other so that the (lGil'lOllIlllztlJlB tread 'lorins one coherent ai'inular ineu'ibor adapted to be dis-- wilcanized to each. other and to the tread "posed. over the tire ca om-is when the tire is deflated and. which. when the tire is iji'illalienl will firmly embrace the periphery oil the tire and be held. by reason oil the ribs 15 from any lateral slipping increment on the tire. These ribs 15 caused by the Wires fll einbed them: selves in. the tire carcass when 'li-l'll": tire is under normal hressure thus liri'nl lu'ilrlingr the detachable or deinoun aliile treciil tr: 1'. side increment or lent l l hen howeren the til this tread magi be readily rein wed. It "will not, llOWE'V become accide ll r detached fron'i the tire when the tire is .erelr' 'l t.

ll O

as holds by reason of the circumferentially extending ribs 15.

It will be seen that my device is extremely simple and practical use has shown it to be thoroughly effective. of this tread, I place the rubber lining 12 over a form. I then place the wires 14 in position and then place over thesewires a plurality of layers of fabric coated with rubber cement and, of course, cemented to the rubber layer 12. In this fabric I embed the steel band 13. I then place over the fabric the rubber tread portion 10, which completes the structure, and when the several parts are vulcanized together I secure a simple and practical tread which is easil put on or taken off when the tire is sla and which is rigidly maintained in its proper position when the tire is under normal pressure.

While I have illustrated a particular embodiment of my invention which I regard as thoroughly effective, I do not wish to be limited to this particular embodiment, as the principle of the invention might be carried out in other ways without departing from the spirit of the invention as defined in the appended claims.

1. A detachable and demountable tread for pneumatic tires annular in form and transversely concave upon its inner face, the tread having embedded therein inward of its inner surface a plurality of circumferentially extending wires on each side of the middle line of the tread forming circumferentially extending ribs on the inner face of the tread adapted to have gripping engagement with the tire upon which the tread is mounted.

2. A detachable and demountable tread for pneumatic tires having a circumferentially extending reinforcing band embedded In the formationin the tread on the middle line thereof, and a plurality of circumferentially extending wires embedded in the tread inward of its inner surface on each side of the band and causing said treadto have a transversely concave-convex form, said wires forming circumferentially extending ribs upon the inner surface of the tread.

3. A detachable and demountable tread for pneumatic tires comprising an inner lining of relatively thin material, an outer relatively thick tread ortion and intermediate layers of fabric, the lining, the fabric and the outer tread portion being vulcanized to each other, a circumferentially extending band embedded in the fabric at the middle line of the tread, and circumferentially extending wires disposed between the lining and the fabric, the lining being outwardly projected by the wires to form a series of oircumferentially extending ribs on the inner face of the tread and on each side of the middle line thereof, the tread having a permanently transversely concavoconvex form;

4. A demountable and detachable tread for pneumatic tires comprising an annular transversely coneavo-convex body formed of laminated elements vulcanized to each other, a circumferentially extending, medially disposed band embedded in the body. and a plurality of circumferentially extendin annuli embedded in the body on each si e of the middle line thereof and inward of the inner face of thebody, the annuli being successively smaller in diameter toward the margins of the body, said annuli forming circumferential ribs upon the inner face of the body.

In testimony whereof I hereunto afiix my signature.

MARCUS A. SHOTWELL. 

